The invention relates to an apparatus having an electrode, a sponge-like, percolating layer, an electrolyte and an element for applying a voltage, as defined in the first claim.
In the publication xe2x80x9cPorous Nickel Oxide/Nickel Films for Electrochemical Capacitors,xe2x80x9d J. Electrochem. Soc., Vol. 143 (1996), pp. 124-130, Kuo-chan Liu and Marc A. Anderson report on electrochemical capacitors. The capacitors comprise two layers that are spaced from one another by 7 mm and are made of percolating, sponge-like NiO/Ni particles, which are applied to a carrier and are 3 to 8 nm in size, with a pore size of 2 to 3 nm. The layers are disposed in an electrochemical cell that is filled with a liquid electrolyte. A first circuit, in which the cell and a resistor are connected in series, charges the capacitor via a potentiostat. The discharge is effected by bridging the potentiostat. A method for producing the layer is disclosed.
Because the two provided percolating layers are separated from one another by a 7 mm-thick layer of the liquid electrolyte, their use is limited to capacitors. Other applications, particularly those based on optical effects, are precluded. The nature of the interaction between the percolating layers and the liquid electrolyte is not described exactly; in particular, it is not mentioned whether the liquid electrolyte penetrates the layers.
xe2x80x9cAn Electrochemical Route for Making Porous Nickel Oxide Electrochemical Capacitorsxe2x80x9d by Venkat Srinivasan and John W. Weidner, J. Electrochem. Soc., Vol. 144 (1997), L210-L213, describes a further production method.
It is the object of the invention to propose an apparatus having a percolating, sponge-like nanoparticulate layer, the apparatus being suitable for numerous technical applications.
The object is accomplished by the apparatus described in claim 1. The further claims disclose preferred embodiments of the apparatus.